1979-2016 Mustang BBK Performance Varitune Exhaust Review

Adjustable Exhaust Sound. Installing a BBK Performance Varitune Exhaust will allow Mustang owners to change the sound and level of their exhaust at any time. The Varitune exhaust incorporates an internal adjustable power valve that is adjusted externally with a wrench. When the valve is in the closed position, the muffler acts as a 3-chamber muffler, regulating the exhaust note down to a regular level. Opening the power valve, however, changes the internal configuration of the muffler into essentially a single chamber design, producing an aggressive, loud note that is typical of a straight-through muffler. Available as a universal muffler or application specific axle-backs, there is an option to fit a BBK Performance Varitune exhaust on any Mustang from 1979-2017.
Aluminized or Stainless Steel Construction. BBK manufactures their Variune Exhaust axle-back and universal mufflers in both aluminized and stainless steel. Aluminized steel is the same material used by Ford on the factory exhaust, and while offering good durability, it will not last as long as stainless. Of course, aluminized steel is less expensive than stainless steel. Stainless steel, on the other hand, is considerably more durable and stronger than aluminum and offers the best protection against corrosion and pitting.
Installation Procedure. Installing an axle-back version of the BBK Performance Varitune Exhaust is a relatively easy job that can certainly be done at home. All Varitune axle-backs are designed as a bolt-on kit, meaning there is no cutting or welding required. The universal mufflers, on the other hand, do require the old muffler to be cut out and the Varitune welded back in its place.

Item # 56240
BBK 4101

Item # 56238
BBK 4100

Item # 56241
BBK 41015

Item # 56239
BBK 41005

Item # 56242
BBK 3101

Item # 56243
BBK 31015

Item # 56244
BBK 3102

Item # 56245
BBK 31025

Item # 56246
BBK 3103

Item # 56247
BBK 31035

[carlneighbors]

Im definitely gettin these for my '07 gt. im also ordering them from you guys at american muscle

[kevinjonker]

I am not quite getting how it becomes a single chamber muffler when the cork is run out? The exhaust is still flowing thruogh every passage in the muffler. Granted it has more of a straight shot toward the last chamber.